Linaloyl pyrophosphate

Suga T, Shishibori T, Morinaka H 1980 Preferential participation of linaloyl pyrophosphate rather than neryl pyrophosphate in biosynthesis of cyclic monoterpenoids in higher plants. J Chem Soc Chem Commun 167-168... 

Ihe preferential participation of linaloyl pyrophosphate rather than... 

Since both neryl pyrophosphate and linaloyl pyrophosphate (or some equivalent species) (34) have been seriously considered as likely acyclic precursors to this family of monoterpenes, it is appropriate to examine first the cationic reactions of these two compounds. A great many investigations have shown that, while geranyl derivatives undergo substitution reactions in a fashion typical of an allylic substrate, both neryl and, less efficiently, linaloyl derivatives lead to cyclic products such as a-terpineol, and its dehydrated relatives limonene, and terpinolene... 

A thorough examination of both the rates and products in the hydrolysis of the pyrophosphates established that linaloyl and neryl pyrophosphates react predominantly by distinct pathways (77—79). The higher yield of cyclic products from neryl pyrophosphate is attributed to anchimeric assistance [an estimated rate enhancement of 2.5 times in the case of (34-OP)] by the 6,7-double bond in the ionization step. Linaloyl pyrophosphate evidently reacts in part from a transoid con-former to give geraniol and from a cisoid conformation to give nerol and cyclic products. 

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